﻿#region Copyright (c) 2009, Active Web Solutions Ltd.
// Copyright (c) 2009, Active Web Solutions Ltd
// All rights reserved.

// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:

// * Redistributions of source code must retain the above copyright
//   notice, this list of conditions and the following disclaimer.

// * Redistributions in binary form must reproduce the above copyright
//   notice, this list of conditions and the following disclaimer in the
//   documentation and/or other materials provided with the distribution.

// * Neither the name of Active Web Solutions Ltd nor the names of its
//   contributors may be used to endorse or promote products derived from
//   this software without specific prior written permission.

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#endregion

using System;
using System.Diagnostics;
using System.IO;
using System.Net.Sockets;
using System.ServiceModel;
using System.Threading;
using Microsoft.ServiceBus;

namespace Aws.SocketShifter
{
    public class SocketShifterClient : IClient
    {
        private NetworkStream networkStream;
        private string issuerName;
        private string issuerSecret;
        private string servicePath;
        private string remoteHost;
        private int remotePort;
        private Thread backgroundThread;
        private TcpClient tcpClient;

        public SocketShifterClient(TcpClient tcpClient, string issuerName, string issuerSecret, string servicePath, string remoteHost, int remotePort)
        {
            this.tcpClient = tcpClient;
            this.issuerName = issuerName;
            this.issuerSecret = issuerSecret;
            this.servicePath = servicePath;
            this.remoteHost = remoteHost;
            this.remotePort = remotePort;    
        }

        private void Toploop()
        {
            // Create the credentials object for the endpoint
            TransportClientEndpointBehavior sharedSecretServiceBusCredential = new TransportClientEndpointBehavior();
            sharedSecretServiceBusCredential.CredentialType = TransportClientCredentialType.SharedSecret;
            sharedSecretServiceBusCredential.Credentials.SharedSecret.IssuerName = issuerName;
            sharedSecretServiceBusCredential.Credentials.SharedSecret.IssuerSecret = issuerSecret;

            DuplexChannelFactory<IServer> channelFactory = new DuplexChannelFactory<IServer>(
                    this,
                    new NetTcpRelayBinding(),
                    new EndpointAddress(servicePath));

            channelFactory.Endpoint.Behaviors.Add(sharedSecretServiceBusCredential);

            IServer server = channelFactory.CreateChannel();

            try
            {
                if (server.Connect(remoteHost, remotePort))
                {
                    Debug.WriteLine("RemoteHost Connected.");
                }
                else
                {
                    Debug.WriteLine("Connection refused.");
                    tcpClient.Close();
                    return;
                }
            } 
            catch (Exception e) 
            {
                Debug.WriteLine(e.ToString());
                tcpClient.Close();
                Debug.WriteLine("Have you configured the Service Bus account details?");
                Debug.WriteLine("Are you sure your SocketShifterServer is running?");
                return;
            }

            networkStream = tcpClient.GetStream();

            try
            {
                int n;
                do
                {
                    byte[] receiveBuffer = new byte[tcpClient.SendBufferSize];
                    n = networkStream.Read(receiveBuffer, 0, receiveBuffer.Length);

                    byte[] sendBuffer = new byte[n];
                    Array.Copy(receiveBuffer, sendBuffer, n);
                    Debug.Write(">");
                    server.Send(sendBuffer);

                }
                while (n > 0);

                Debug.WriteLine("TcpClient Disconnected.");
            }
            catch (IOException e)
            {
                // Maybe the server forcibly closed the connection?
                Debug.WriteLine(e.ToString());
            }
            finally
            {
                networkStream.Close();
                networkStream.Dispose();
                server.Disconnect();
                tcpClient.Close();
            }
        }

        public void Start()
        {
            backgroundThread = new Thread(new ThreadStart(Toploop));
            backgroundThread.Start();
        }

        public void Stop()
        {
            backgroundThread.Abort();
        }

        // This is the callback method, called by the server
        public void Receive(byte[] buffer)
        {
            Debug.Write("<");
            try
            {
                networkStream.Write(buffer, 0, buffer.Length);
            }
            catch (IOException e)
            {
                Debug.WriteLine(e.ToString());
            }
            catch (ObjectDisposedException e)
            {
                Debug.WriteLine(e.ToString());
            }
        }

    }
}
